(a) Field of the Invention
The present invention relates to a virtual radio map constructing method for Radio-positioning and a device using the same, and more particularly, to a virtual radio map constructing method and a device using the same that may simply construct a radio map.
(b) Description of the Related Art
Due to remarkable development of a mobile communication technology and spread of smartphones, a location based service (LBS) technology has been actively researched. Recently, since all smartphones includes a chip that can perform outdoor Radio-positioning by using a GPS and a mobile communication network, a LBS market has rapidly grown. However, the outdoor Radio-positioning technique using the GPS or the mobile communication network provides high precise location information outdoors, but since signal loss greatly occurs indoors or in shaded areas, precision of the Radio-positioning therein may rapidly decrease.
Accordingly, in order to improve precision of indoor Radio-positioning, techniques using received signal strength (RSS) of a WiFi access point (AP) that is widely installed indoors have been actively researched. The indoor Radio-positioning using the RSS includes a parameter method based on a radio model and a non-parametric method based on training data. The most popular method of the indoor Radio-positioning is the non-parametric method of a fingerprinting Radio-positioning method.
The indoor fingerprinting Radio-positioning method includes a radio map (RM) constructing step of collecting a RSS value at a reference point and a Radio-positioning step of estimating movement of a terminal by using the radio map.
As a typical a radio map constructing method through fingerprinting, a method of collecting a RSS value through training at each reference point is referred to as a static RM. The static RM continues to use the once measured value without updating it.
However, since an indoor wireless channel environment is changed depending on time, movement of an object, or the like, the RSS value changed according to an environment should be corrected in order to ensure precise positioning performance. However, whenever the environment is changed, it is not economical to construct the RM by obtaining a new RSS. Further, it is inefficient to obtain the RSS by measuring it several times at each reference position of a spacious indoor space, and the denser the reference positions are, the more the amount of labor and time is required to measure the RSS.
Background technology of the present invention is disclosed at Korean Patent No. 1390722 (Apr. 30, 2014).
The above information disclosed in this Background section is only to enhance the understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.